package com.transaction.utils;

import java.security.MessageDigest;

/** 
 *description:MD5工具类
 *@author wangbing
 *@date 2015年11月20日下午2:44:19
 */
public class MD5Util {
	    private final static String[] hexDigits = {"0", "1", "2", "3", "4", "5", "6", "7",
	            "8", "9", "a", "b", "c", "d", "e", "f"};

	    /**
	     * 转换字节数组为16进制字串
	     * @param b 字节数组
	     * @return 16进制字串
	     */
	    public static String byteArrayToHexString(byte[] b) {
	        StringBuilder resultSb = new StringBuilder();
	        for (byte aB : b) {
	            resultSb.append(byteToHexString(aB));
	        }
	        return resultSb.toString();
	    }

	    /**
	     * 转换byte到16进制
	     * @param b 要转换的byte
	     * @return 16进制格式
	     */
	    private static String byteToHexString(byte b) {
	        int n = b;
	        if (n < 0) {
	            n = 256 + n;
	        }
	        int d1 = n / 16;
	        int d2 = n % 16;
	        return hexDigits[d1] + hexDigits[d2];
	    }

	    /**
	     * MD5编码
	     * @param origin 原始字符串
	     * @return 经过MD5加密之后的结果
	     */
	    public static String MD5Encode(String origin) {
	        String resultString = null;
	        try {
	            resultString = origin;
	            MessageDigest md = MessageDigest.getInstance("MD5");
	            md.update(resultString.getBytes("UTF-8"));
	            resultString = byteArrayToHexString(md.digest());
	        } catch (Exception e) {
	            e.printStackTrace();
	        }
	        return resultString;
	    }

	   
}
